FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION
A NOVEL METHOD OF PROTECTING ENGINE AND FUEL INJECTION EQUIPMENT FROM DETERIORATION DUE TO USE OF BIO-DIESEL IN DIESEL ENGINE
2. APPLICANT
MAHINDRA & MAHINDRA LTD.
1, GATEWAY BUILDING, APOLLO BUNDER, MUMBAI - 400001. AN INDIAN COMPANY.
The following specification particularly describes the invention and the manner in which It is to be performed.

FIELD OF THE INVENTION:
The present invention relates to a cleaning system for internal combustion engines fuelled by diesel and/ or biodiesel, and particularly, to a method of protecting engine components from deterioration due to the presence of acidic constituents in biodiesel, when we use it as working fuel, and more particularly, relates to a fuel cleaning system of engines having biodiesel as a working fuel and conventional diesel (HSD) as a cleaning agent/fuel for a preset period of time before shut down the engine as well as starting the engine in applications such as generator sets, where the engine is operated intermittently or kept standby for long time intervals.
BACKGROUND OF THE INVENTION:
Generally, biodiesel can be used commercially in different applications. One of the major applications is as combustible fuel in internal combustion engine. The present invention is concerned with certain operating problems in an internal combustion engine, particularly fuelled by biodiesel. One such problem is that when engine fuelled by biodiesel is kept idle without running for long period of time, the acidic constituents present in biodiesel tend to corrode the surfaces of the engine components such as engine cylinder walls, piston, piston rings, valve seats as well as the fuel passages (pipes) and Fuel Injection Pump. There is also likelihood of the acids or acidic constituents leaking through the corroded rings into the oil sump where they are pumped throughout the engine. This will cause some undesirable effects on engine; particularly shorten the life of engine in such applications where the engine is used (run) intermittently.

For example, in genset applications it is obvious that engines are operating intermittently; in such cases the biodiesel content present in the engine for long time leads to formation of acids due to reaction of moisture content and the hydrocarbons present therein, which may also cause fuel aging and engine oil dilution. Unless this biodiesel is removed after shutdown of the engine meant for keeping idle (without running) for longer intervals, it will lead to fuel filter clogging, deposit formation inside the entire fuel injection pump and sticking of moving parts. These further lead to injector choking, degradation in the engine performance and further shorten the life of engine. Various inventions have been developed for cleaning and conditioning the internal combustion engines fuelled by various fuels in diverse applications for improving the performance or reliability of the engine, some of which are described below;
US patent 5724948 discloses a biogas driven generator set in which an acid neutralizing oil is introduced into engine intake manifold each time when engine is shut down to prevent corrosion of engine. According to this invention, protection from corrosion is limited to only engine components since said oil is injected directly into intake manifold. Related engine components are not getting protected and which may cause overall performance of engine and frequent service and/or replacement of other related engine components also chances are more that said oil may mix up with fuel and/or lubrication oil. This will further affect the performance of engine. Also, the timer which mentioned in this invention has to control pump as well as solenoid valve to activate the cleaning system which further makes entire system complex.

US patent 6964254 discloses an apparatus and method of conditioning an engine for storage, which automatically introduces predetermined amount of lubrication oil into an internal combustion engine for coating the inside components of engine thereby to avoid rust and condensation of metal surfaces of engine components that may result during extended period of non operation. This particular invention is also directly injecting the lubricating oils to air intake via an oil injector same as patent US5724948. And, the ECU has to be precisely controlled to control first amount of oil and second amount of oil to be introduced in the engine. Any fault in the ECU may result in mixing of oil with fuel which will severely affect the combustion process of engine thereupon reliability. Also, it involves high cost to develop such kind of cleaning or conditioning for engine.
US patent 7231930 discloses a cleaning system in use with propane burning engine to clean needles and other internal components found in regulator and lock-off valve assembly. According to this invention, there is no control over the addition of carburettor cleaning fluid with propane liquid since it is manually controlled whenever there is a need to clean the valve.
While aforementioned prior patents accomplish their respective objects and requirements, the need remains for a cleaning system that should overcomes the shortcomings of above mentioned prior arts and provide a reliable and cost effective method for removing or cleaning the internal combustion engine and entire fuel supply system off the biodiesel which otherwise will cause deterioration of engine and related components thereof if the engine is kept for long time with no use.

OBJECT OF THE INVENTION:
The present invention overcomes the shortcomings associated with the background art and achieves other advantages not realized by the background art.
The main object of the invention is to provide a method/ process for cleaning the internal combustion engine and components thereof coming in contact with the biofuel, by running diesel fuel as cleaning agent as well as working fluid, while stopping and starting the engine. Another object of the invention is to use pure biodiesel hereinafter called B100 or any biodiesel blends (0 to 100 % biodiesel mixed with diesel) as working fuel especially in application where engine is required to run intermittently.
Yet another object of the invention is to provide a cleaning system so as to keep the engine idle or non-operative for a week or more even with the use of B100 without affecting the engine performance and life.
Yet another object of the invention is by providing conventional diesel as cleaning agent, problems arises due to the use of various oils as cleaning agent and mixing it with working fuels like described in prior patents can be avoided.
Yet another object of the present invention is to provide a method for cleaning internal combustion engine and surfaces of all engines components coming in contact with fuel so as to avoid the formation of acid due to the reaction of hydrocarbon with moisture content

being present in the biodeisel, which will otherwise cause corrosion and deterioration of such engine components, further leading to degradation in engine performance.
Yet another object of the invention is to provide a cleaning system in which the diesel will run for preset period of time while shut down or starting the engine as a cleaning agent so as to perform like any other engine run by diesel.
Yet another object of the present invention is enabling running the engine with upto B100 (pure biodiesel) as working fuel, by which environmental pollution can be reduced compared with conventional use of biodiesel blends.
In accordance with the present invention, the cleaning system comprises;
a first container to carry diesel fuel and for supplying while shut down and starting the engine, a second container to carry biodiesel fuel as working fuel for the operation of engine, first solenoid valve & second solenoid valve to control the flow of diesel and biodiesel respectively to engine and a electronic control system to control the actuation of solenoid valves selectively. The cleaning system is performed by introducing diesel fuel while shut down and starting the engine for a preset period of time to remove the biodiesel which used to run for the normal operation of engine. The switch-over from biodiesel to diesel at the time of stopping the engine and that back to biodiesel at the time of restarting is automatically managed with solenoid valve thus eliminating need for any manual control or intervention. Also, the aforementioned flushing cycle (by running

the engine with diesel to flush the biodiesel out) is performed on-line while the engine is running and hence there is no need to stop the engine operation in order to carry out the flushing operation off-line. The invention thus enables use of 0 to 100%
Further scope of applicability of the present Invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS:
The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG.l is a block diagram of cleaning system according to present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT:
In the following, an embodiment of the present invention is described with reference to the drawings.
With Reference to FIG.l, the preferred embodiment describes the concepts and principles of the present invention, a cleaning system for internal combustion engines fuelled by biodiesel and related components thereof for protection from deterioration due to the intermittent nature of operation in electric generator application, generally designated by reference numeral 16 below.
As best illustrated in FIG. 1, the cleaning system 16 comprises a first reservoir 2 for containing biodiesel and as a source for supplying fuel for the operation of the engine. The reservoir 2 is provided with two ports of which one port serves as an outlet (12) has and another port serves as an inlet (13). The cleaning system 16 also comprises a second reservoir 1 for containing conventional diesel which acts as cleaning agent according to our present invention. A first conduit 17 having first end thereof is fluidly connected to outlet 12 of first reservoir 2 and fluidly coupled with a first filter 3, a water separator 5 and a first solenoid valve 7 operatively. A second conduit 18 having first end thereof is fluidly connected to outlet 14 of second reservoir 1 and fluidly coupled with a second filter 4 and a second solenoid valve 6 operatively.
Second end of first conduit 17 and second end of second conduit 18 is fluidly connected with a connector means 15 and extended as a single conduit 19 therefrom and free end thereof is fluidly connected with fuel feed pump 8. The fuel feed pump 8 pump the fuel to fuel injection pump 9 from there fuel goes to engine 10 like

any other conventional internal combustion engines . A fuel channel 20 having one end thereof is fluidly connected with inlet 13 of first reservoir 2 and another end thereof is selectively fluidly connected with fuel injection line 21 as shown in FIG.l. The cleaning system also comprises an electronic control system 11 for operatively energizing the solenoid valves in accordance with the present invention.
With referring to FIG.l, the operation of the cleaning system, according to the present invention will be described in detail. The biodiesel coming out from the first reservoir 2 is passing through the first filter 3 where the particles or the solid contaminants, if any, present in the biodiesel gets filtered out. This filtered biodiesel then goes to water separator 5. Here the moisture content produced during the production of biodiesel gets separated and collected in the bottom of the separator 5. The biodiesel which is coming out of the separator directly goes to fuel feed pump 8. The flow of biodiesel is controlled by first solenoid valve 7 which is electronically controlled by control system 11.
The fuel which is coming out from the second reservoir 1 through the outlet 14 is passing through second filter 4 where the diesel fuel gets filtered out from other solid contaminants. The fuel which is coming out from the filter is directly goes to fuel feed pump 8. The flow of diesel is controlled by second solenoid valve 6 which is electronically controlled by control system 11.

The present invention illustrated herein the embodiment is a process in such a way as to clean or remove the biodiesel which is used to power the engine, by running diesel as working fuel and/or cleaning agent at the time of shutting down and/or start the engine for a preset period of time so as to remove the biodiesel content from the entire fuel system as well as the engine. This will avoid the corrosion of the conduits and other related engine components and the wear of engine components. By keeping this objective as our particular invention, the embodiment enclosed here explains two electronically controlled, normally closed, solenoid valves. When the engine is started, the second solenoid valve 6 gets activated and allows the diesel fuel to flow into the fuel feed pump 8 which pump the fuel to fuel injection pump (9) from which the fuel goes to the engine 10. A timer is provided in the control system (11) to set the time period in such a way that only diesel will run for the preset period of time. Then the second solenoid valve 6 gets deactivated and at the same time the first solenoid valve 7 gets activated to allow biodiesel to flow into the engine. Similarly when the engine is shutting off, first solenoid valve 7 gets deactivated and second solenoid valve 6 gets activated for allowing the diesel fuel to flow into the system. Thus the biodiesel content present in the fuel injection equipments gets removed and only some amount of diesel is present while shutting off the engine. Eventually the above described fuel system illustrated in the preferred embodiment behaves like conventional diesel engine.

It will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed in the foregoing description. Accordingly, the particular embodiments described in detail herein are illustrative only and are not limiting to the scope of the invention, which is to be given the full breadth of the appended claims and any all equivalents thereof.

We claim:
1. A cleaning system for use with an internal combustion engine fuelled by biodiesel and a fuel supply system for cleaning said internal combustion engine and related components thereof, the fuel supply system being of the type including a first reservoir for containing sufficient quantity of biodiesel to fuel said internal combustion engine, and a first conduit fluidly connected with said first reservoir and a connector means, and a third conduit fluidly connected with said connector means and a fuel feed pump, and a first control valve in fluid communication with said first conduit in such a way that biodiesel will flow through said first conduit and said third conduit to said internal combustion engine via said first control valve selectively, said cleaning system comprising:
a second reservoir for containing sufficient quantity of cleaning fluid and provided with an outlet for introducing said cleaning fluid for fuelling said internal combustion engine as well as for serving as a cleaning fluid each time shut down the engine through a second conduit, wherein said conduit is fluidly connected with said second reservoir and said connector means and fluidly communicated with a second control valve such that said cleaning fluid flowing through said second conduit and said third conduit to said internal combustion engine via said second control valve, selectively, to engine so as to remove biodiesel content present previously in said internal combustion engine and related components thereof;
a control unit to energize said first control valve and said second control valve for a preset period of time so as to control the flow of biodiesel and said cleaning fluid to said internal combustion engine.

2. The cleaning system claimed in claim 1, wherein said control unit is electronically controlled unit.
3. The cleaning system claimed in claim 1, wherein said cleaning fluid is conventional diesel fuel.
4. The cleaning system claimed in claim 1, wherein said control unit is provided with timer for activation and deactivation of said control valves for preset period of time.
5. The cleaning system claimed in claim 1, wherein said first control valve is first solenoid valve.
6. The cleaning system claimed in claim 1, wherein said second control valve is second solenoid valve.
7. The cleaning system claimed in claim 1, wherein said first conduit Is fluidly communicated with a first filter and a, water separator.
8. The system claimed in claim 1, wherein said second conduit is fluidly communicated with a second filter.
9. The system claimed in claim 1, wherein said connector means comprises atleast three ports for fluidly coupling second end of said first conduit and second end of said second conduit and first end of a third conduit.

10. In combination:
an internal combustion engine fuelled by biodiesel;
a fuel supply system in fluid communication with said internal combustion engine constructed to fuel biodiesel to said internal combustion engine for operation thereof;
a cleaning system in fluid communication with said fuel supply system and said internal combustion engine constructed to clean said internal combustion engine and related components thereof from biodiesel contents by introducing a cleaning fluid.
11. The combination claimed in claim 6, wherein said fuel supply
system comprises:
a first reservoir for containing sufficient quantity of biodiesel to fuel said internal combustion engine;
a first conduit having first end fluidly connected with said first reservoir and second end fluidly connected with a connector means;
12. The combination claimed in claim 7, wherein said first conduit is fluidly communicated with a first filter, a water separator and a first solenoid valve.
13. The combination claimed in claim 8, wherein said first solenoid valve is controlled by a control system and a timer is provided with said control system to set the time for energizing said first solenoid valve so as to permit or prevent the flow of biodiesel to said internal combustion engine.

14. The combination claimed in claim 6, wherein said cleaning
system comprises:
a second reservoir for containing sufficient quantity of cleaning agent and provided with an outlet for introducing said cleaning agent to said interna! combustion engine;
a second conduit fluidly connected with said second reservoir and said connector means;
15. The combination claimed in claim 10, wherein said cleaning agent is conventional diesel fuel.
16. The combination claimed in claim 10, wherein said second conduit is fluidly communicated with a second filter and a second solenoid valve.
17. The combination claimed in claim 10, wherein said connector means is provided with atleast three ports for fluidly connecting second ends of said first conduit and said second conduit and first end of a third conduit, wherein second end of third conduit is fluidly connected with a fuel feed pump.
18. The combination claimed in claim 10, wherein said second solenoid valve is controlled by said control system and said timer is provided with said control system to set the time for energizing said second solenoid valve so as to permit or prevent the flow of cleaning agent to said internal combustion engine.

19. The combination claimed in claim 6, wherein said fuel supply system comprises:
a first reservoir for containing sufficient quantity of biodiesel to fuel said internal combustion engine;
a first conduit having first end fluidly connected with said first reservoir and second end fluidly connected with a connector means;
wherein said first conduit is fluidly communicated with a first filter, a water separator and a first solenoid valve.
wherein said first solenoid valve is controlled by a control system and a timer is provided with said control system to set the time for energizing said first solenoid valve so as to permit or prevent the flow of biodiesel to said internal combustion engine.
wherein said cleaning system comprises:
a second reservoir for containing sufficient quantity of cleaning agent and provided with an outlet for introducing said cleaning agent to said internal combustion engine;
a second conduit fluidly connected with said second reservoir and said connector means;
wherein said cleaning agent is conventional diesel fuel.
wherein said second conduit is fluidly communicated with a second filter and a second solenoid valve.

wherein said connector means is provided with atleast three ports for fluidly connecting second ends of said first conduit and said second conduit and first end of a third conduit, wherein second end of third conduit is fluidly connected with a fuel feed pump.
wherein said second solenoid valve is controlled by said control system and said timer is provided with said control system to set the time for energizing said second solenoid valve so as to permit or prevent the flow of cleaning agent to said internal combustion engine,
20. In combination:
an internal combustion engine fuelled by biodiesel;
a fuel supply system in fluid communication with said internal combustion engine constructed to fuel biodiesel to said internal combustion engine for operation thereof, said fuel supply system comprising:
a first reservoir for containing sufficient quantity of biodiesel to fuel said internal combustion engine;
a first conduit having first end fluidly connected with said first reservoir and second end fluidly connected with a connector means, said first conduit is fluidly communicated with a first filter, a water separator and a first solenoid valve, said first solenoid valve is controlled by a control system and a timer is provided with said control system to set the time for energizing said first solenoid

valve so as to permit or prevent the flow of biodiesel to said internal combustion engine.
a cleaning system in fluid communication with said fuel supply system and said internal combustion engine constructed to clean said internal combustion engine and related components thereof from biodiesel contents, said cleaning system comprising:
a second reservoir for containing sufficient quantity of cleaning agent and provided with an outlet for introducing said cleaning agent to said internal combustion engine; said cleaning agent is conventional diesel fuel;
a second conduit fluidly connected with said second reservoir and said connector means; said second conduit is fluidly communicated with a second filter and a second solenoid valve, said connector means is provided with atleast three ports for fluidly connecting second ends of said first conduit and said second conduit and first end of a third conduit, wherein second end of third conduit is fluidly connected with a fuel feed pump, said second solenoid valve is controlled by said control system and said timer is provided with said control system to set the time for energizing said second solenoid valve so as to permit or prevent the flow of cleaning agent to said internal combustion engine.